Film



Aug. 31 1926.

M. DESPERATI FILM Filed Oct. 19,

SENJI 77250 L A YER R w A L m a w m m WIT/1 GROUND -L IKE AY CO/WW/VAir/4794147704 6010/?) CELLULOID SUPPORT Lvenfar':

iffarn Patented Aug. 31, 1926.

UNITED STATES PATENT OFFICE.

W0 DE SPEBATI, OF TURIN, ITALY, ASSIGNOB TO I. G. FABBENINDUSTRIE'AKTIENGESELLSCHAFT, 0F FBANKFOBT, GERMANY.

rims.

Application filed October 19, 1923, Serial 1T0, 668,552, and in ItalyOctober 20, 1922.

The present invention relates to filmsfor photographic and motionictures, and has for its object a film comprising a transparent support,a sensitized layer on one face of said support and a translucent groundlayer on the other face of the same support.

Layers or coatings have heretofore been pro osed to prevent halation orcurling or ot or to scatter visualv rays in X-ray work; but most ofthese coatings great inconvenience in handling the ter development, i.e., during printing, and none of them was by any means suitable inpzinting. Various coatings have therefore en devised in the past, whichare readily removable, or which may be altered after develo ment in someway to enable printing.

T e present invention relates t a layer or coatin on photographic filmwhich answers not on y'two but three requirements, in that it preventshalation and curling and affords at the same time and without anyalteration a suitable ground for retouching.

A film according to the resent invention has a very extensive antialocharacter in view of the said ground layer which assists efliciently inthe absorption of the light passing through its sensitized layer and itssupport, and the presence of said ground layer prevents the film fromrolling or curling in the baths, in the known manner; further thesurface of said ground layer is-adapted to receive retouches which maybe produced in the most satisfactory manner because they may be erasedfrom said ground surface when incorrect and made up again, said groundlayer being not liable to e injured by pencil and soft erasers.

In a preferred embodiment of the present invention a film of thedescribed character comprises a transparent layer which adheres to thesupport and has crystals or grains of exceedingly'small size embedded initand which make it translucent with a groundlike surface; a furtherembodimentcomprises a film having a layer of the described character inwhich is embedded a substance resent lm afada ted to increase theanti-halo character of t e same In er.

The single represents by way of example and on enlarged scale asectional view of a film according to the resent invention.

In said sect1on,.1- is a supporting film which is conveniently made ofcelluloid, as

gure of the annexed drawing conventional, while 2 is a sensitized layerlocated on one face of said film 1 and which preferably is a layer ofgelatin sensitized by means of a silver salt as silver bromidf 3 is alayer located on the other face of the film 1 and which consists of atransparent material adapted to adhere to the celluloid support, aselatin, in which are incorporated exceeding y small grains which causeit to show a ground-like surface and to become translucent. Resins andcolloid materials have been found to be particularly useful for thisscope.

As stated, said layer may also contain a substance adapted to magnifyits antihalo action.

Hereinafter is particularly described by way of example a method ofproducing a film of the described character.

A solution is prepared as follows:

Parts by I weight. Amyl acetate 120 Acetone 90 Celluloid 1 Anothersolution is prepared as "follows: Ether 100 c. c., powdered sandarac 12s., Dammar gum 4. gms., benzene 60 gms.

Then the first solution is added to the second one, the mixture beingslowly stirred.

This mixture is spread or distributed on one face of a film and then itis left to dry.

The layer thus produced on the film has embedded in it exceedingly fineand small grains of resinous material and thus it shows'a ground-likesurface which is quite adapted to receive retouches made by means ofpencil and stumps and permits of eras-' ing the same by means of a softrubber eraser.

Further said layer is impervious to water and therefore the film may anydesired treatment in baths without said layer being apt to becomeinjured or to show stains which would be reproduced on prints madetherefrom.

Another example of a mixture adapted to produce a layer of the describedcharacter is as follows:

Water 100 c. 0., hard gelatin 8 gms., corn starch 3 gms., phenic acid0.5 c.'c.-

With this mixture a. similar result as above described is obtained.

An amount of a substance adapted to inbe submitted to p crease theanti-halo action of the said layer may be added to it; say aurantia maybe used, an amount of this substance as 10 c. c. of a l solution ofaurantia being added to either of the above described mixtures.

Other antihalo substances as red ocher or anilin colors may also be usedfor the same purpose.

The film according to the present invention may be used for anyphotographic process and it is particularly useful in producingcolour-selected negatives for tri-chromic processes.

What I claim as my invention and desire to secure by United StatesLetters Patent 1s 2-- 1. A film for photography with visible rays,comprising a transparent support, a sensitized layer on one face of saidsupport, and a layer on the other face of said support; the last-namedlayer being permanently associated with the support and having aground-like surface which is capable of receiving retouches. a

2. A film for photography with visible rays, comprising a transparentsupport, a sensitized layer on one face of said support, and a layer onthe other face of said support; the last-named layer being permanentlyassociated with the support and containing small grains which render itssurface rough and capable of receiving retouches.

3. A film, comprising a trans arent support, a sensitized layer on oneace of said support, and a layer on the other face of said support; thelast-named layer being permanently associated with the support andhaving a ground-like surface and containing an anti-halo substance, saidsurface being capable of receiving retouches.

4. A film for photography with visible grains which render its surfacerough and capable of receiving retouches.

6. A film for photography with visible rays, comprising a transparentsupport, a sensitized layer and a permanent layer of gelatin on theother face of said support; the last-named layer having small grains ofcorn starch embedded in it which render its surface rough and capable ofreceiving retouches.

7. A film, comprising a transparent support, a sensitized layer on oneface of said support, and a permanent layer on the other face of saidsupport; the last-named layer having small grains of corn starchembedded in it to render its surface capable of receiving retouches, andcontaining an anti-halo substance.

8. A film, comprising a transparent support, a sensitized layer on oneface of said support, and a layer on the other face of said support; thelast-named layer being permanently associated with the support andhaving a ground-like surface which renders it capable of receivingretouches, and containing an amout of aurantia.

In testimony whereof I affix my signature.

MARIANO on SPERATI.

on one face of said support,

